Hi Dustin, There is always a chance that you could need to build yourself a new license file, it just depends if your computer's host ID and host name change during your upgrade. If it does change, you can build yourself a new license through the online tool if you are current on maintenance. Currently, no versions of IDL are supported for Windows 10, but IDL 8.5 will be supported on Windows 10 when it is released in a few months. If you are current on maintenance then you can also upgrade to the latest and greatest version of IDL which is always a good idea to do for bug fixes and other improvements that are made.